After giving up a back-to-back singles to Rajai Davis and Maicer Izturis, he started Emilio Bonifacio with three straight balls.

After seeing Lester slip on the mound, manager John Farrell knew something was wrong. He came out with a trainer to check on his ace.

The Sox’ rotation is already teetering with Clay Buchholz sitting out with lingering soreness in his shoulder.

Seeing Lester leave after throwing seven-plus innings in the Red Sox’ 7-4 win over the Blue Jays with a jammed right hip, part of Saltalamachcia wanted to be worried.

At the same time, part of him knew better.

“He’s a strong guy,” Saltalamacchia said. “I’ve never seen him come out and let it affect his next start. He’s a workhorse.”

Farrell said the decision was precautionary. And although he felt a stinging sensation as he walked to the dugout, Lester said he felt fine afterward.

Asked if he was relieved, Farrell said, “Absolutely.”

Coming into this four-game set with the Jays, Farrell knew it would be a challenge.

It had only been a month since the teams last met. In mid-May, the Jays seemed smothered by preseason expectations. Even after taking two of three at Fenway, they were nine games under .500 and 9½ games behind the Sox in the division. Only five teams had scored fewer runs up to that point, and the only team to allow more was the Houston Astros, the league’s unanimous punching bag.

It took a while, but things eventually clicked for Toronto. The bats woke up. The Jays ripped off a major league-high 11-game winning streak earlier this month, and came into Fenway on Thursday having won 15 of their last 19.

From afar, the Red Sox noticed it all.

“I think everybody in the game saw them to be a very strong team,” Farrell said. “Just from the outside looking in, they’re pitching much more consistent. Their bullpen has been outstanding. So the fact that they’re above .500 and they’re clearly in the hunt in this division is not surprising, I don’t think, to anyone.”

But with a seven-run, seven-hit second inning, the Sox cooled off the Jays.

The Sox batted around as Daniel Nava, Saltalamachcia, Stephen Drew, Jose Iglesias, and Jacoby Ellsbury drove in runs in succession, and Dustin Pedroia blew the inning open with a two-run homer that helped the Sox cruise to their seventh win in their past eight games at Fenway.

Jays manager John Gibbons was digging into his bullpen early.

Starter Chien-Ming Wang lasted just 1⅔ innings. It was his worst start since the Indians shook him up for eight runs on eight hits four years ago as a Yankee.

Pedroia delivered the knockout punch, jumping on a knee-high, two-strike slider and blasting it over the Green Monster for his fifth homer of the season.

“We understand the talent that they have on their team,” Pedroia said. “They’ve got a solid pitching staff and guys that hit the ball out of the ballpark and speed. They’re a really good team. That’s why you play 162 games. We knew it was only a matter of time until they got on a hot streak.”

No one on the Sox has picked on the Jays more this season than Pedroia, who is hitting .381 (16 for 42) against Toronto.

“Whether or not there’s been some pitches that were mislocated on the plate — it was an 0-2 split that Wang tried to bury to put him away, but he leaves it up in the strike zone — whether it’s that given pitch or what their overall approach [is] to try to attack Dustin, I know he’s faced those guys a number of times and he’s a good hitter. It’s not just the Blue Jays that he’s successful against,” Farrell said.

Thanks to the big inning, Lester could breathe easy.

In his previous three starts Lester had given up 17 runs over 15⅓ innings. On Thursday night he went seven-plus innings, giving up four runs on five hits.

“Obviously having a seven-run lead in the second helps,” Lester said. “When you have a seven-run lead against these guys, it just takes that pressure off for making perfect pitches. You’re able to go out there, you know they’re going to be aggressive and you just have to try to keep the ball down and keep it in the park and we were able to do that.”

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